The energy required to completely separate the ions from a solid is
(a) free energy
(b) lattice energy
(c) kinetic energy
(d) activation energy
(e) ionization energy

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

Answerhund's rule;

Answersublimation;